1. Field of the Invention
Apparatuses and methods consistent with the present invention relate to a semiconductor probe and a method of fabricating the same and, more particularly, to a semiconductor probe with a high resolution resistive tip having a doping control layer for controlling distribution of impurities and a method of fabricating the semiconductor probe.
2. Description of the Related Art
As the demand for portable devices such as mobile phones increases, the demand for small-sized, high-integration non-volatile recording media also increases. It is difficult to reduce the size of a conventional hard disk and it is difficult to increase conventional flash memory integration. Therefore, in recent years, much research has been done concerning an information storage device using a scanning probe.
A probe is used in a variety of scanning probe microscopy (SPM) technologies. For example, the probe is used in a scanning tunneling microscope (STM) for reading information by detecting a current that flows according to a voltage difference between the probe and a sample, an atomic force microscope (AFM) for reading information by using an atomic force generated between the probe and the sample, a magnetic force microscope (MFM) for reading information by using a force generated between a magnetic field of the sample and the magnetized probe, a scanning near-field optical microscope (SNOM) for improving a resolution limitation caused by a wavelength of a visible ray, an electrostatic force microscope (EFM) for reading information by using an electrostatic force generated between the sample and the probe, and the like.
In order to write and read information densely at a high speed using the STM technology, it must be possible to detect surface electric charges existing in a region having a diameter of tens of nanometers. In addition, in order to improve the writing/reading speed, it must be possible to fabricate a cantilever in an array structure.
A conventional cantilever having a resistive tip is disclosed in PCT publication No. WO 03/096409.
FIG. 1 is a sectional view of the related art cantilever with the resistive tip.
A resistive tip 10 is vertically arranged on a cantilever 11 in an array structure. Referring to FIG. 1, the resistive tip 10 includes a body 14 doped with first impurities, a resistive region 13 formed on an apex of the tip 10 and doped with second impurities, and first and second semiconductor electrodes 12 and 15 between which the resistive region 13 is formed. The resistive region 13 has a diameter of tens of nanometers. The first and second semiconductor electrodes 12 and 15 are doped with the second impurities.
In the process of forming the resistive tip 10, the first and second semiconductor electrodes 12 and 15 formed on the inclined surface of the tip 10 are excessively wet-etched, thereby reducing the area of the inclined surface that is heavily doped. Therefore, the conductive area is reduced in the inclined surface, resulting in the spatial resolution of the resistive region 13 deteriorating. In addition, in the fabrication process, a portion where the probe will be formed after the etching process is performed may be damaged due to a relatively high ion implantation energy of about 300 keV. Furthermore, there is a need to perform not only a thermal diffusion process, i.e., an annealing process at 1000° C. for 12 hours, but also a thermal oxidation process at 1000° C. for 30-40 minutes.